The invention relates to the cleaning of hard surfaces with non-corrosive, low-fuming compositions. More particularly, the invention relates to non-corrosive, low-fuming oven cleaning compositions. Still more particularly, the present invention relates to a method of cleaning vertical surfaces with a non-corrosive, low-fuming composition.
During food preparation, the use of ovens both at home and in commercial kitchens are standard. Depending upon the cooking process, food may be cooked directly on the oven surface or it may be placed within the oven in a container during cooking. In both processes food products contact and inevitably get baked on to the oven surface. This baked on soil becomes even more difficult to clean if it is allowed to build up during successive heating cycles within the oven.
To clean these difficult soils, prior art cleaners rely heavily upon caustic components to achieve sufficient cleaning. The use of caustic components, while being effective to remove tough soils, results in compositions that may not be safe for the end-user.
To address these safety issues, non-corrosive alternatives to these cleaners have been developed. Commercially available non-corrosive products are also available as fume free products. However, prior art non-corrosive products, such as the prior art fume free products, generally provide cleaning which is inferior to the cleaning that can be achieved with corrosive oven cleaning products. Furthermore, while claiming to be fume free, prior art fume free products often must be used at ambient temperature to avoid fumes that may be produced at higher temperatures Accordingly, even xe2x80x9cfume freexe2x80x9d products may produce fumes that are irritating to the user of the product.
The present invention overcomes these disadvantages associated with the prior art, by providing a low-fuming, non-corrosive, low caustic level cleaner that can be used to efficiently remove baked on soils. The composition of the present invention can be used easily on the vertical wall surfaces of an oven either at ambient or elevated temperatures.
In accordance with one aspect of the invention there is provided a method of cleaning a food surface by applying a non-corrosive low-fuming composition to the surface. The composition includes a detergent builder, an alkalinity source to provide a compositional pH of from about 10 to 14, a thickening agent to promote thickening and adhesion of the non-corrosive, low-fuming composition to the surface upon application, and a balance of water. The composition is substantially free of chlorinated products.
In accordance with a further aspect of the invention, there is provided a thickened oven cleaning composition comprising a detergent builder, a thickening agent to provide increased viscosity, a source of alkalinity to provide a compositional pH of about 10 to 14, a surfactant to provide detergency to the composition, and a balance of water.
In accordance with an alternative aspect of the invention, there is provided a method of cleaning a substantially vertical surface with an adherent, thickened, low-fuming, non-corrosive composition. The method comprises applying the composition to the substantially vertical surface. The composition includes from about 0.1 wt-% to about 20.0 wt-% of a detergent builder, from about 0.1 wt-% to about 5 wt-% of a thickener, from about 0.1 wt-% to about 20 wt-% of an alkali source providing a compositional pH of greater than about 10, and a balance of water. The composition has a Brookfield viscosity ranging from about 30 to 10,000 Cps at 25xc2x0 C. Brookfield viscosity refers to an art recognized measurement method with the viscosity being measured using an appropriate spindle and speed to obtain optimum accuracy. Upon application, at least about 75 wt-% of the applied cleaner adheres to the surface of application for at least about 30 minutes.
The invention includes methods and composition for cleaning oven surfaces. The invention provides a sprayable, adherent, non-corrosive, low-fuming cleaning composition. The invention provides a composition which is adherent to the surface of application even when positioned substantially vertically. Up to about 75 wt-%, preferably up to about 85 wt-% and most preferably up to about 95 wt-% of the applied composition may be retained on the surface of application after about 30 minutes at ambient temperatures, when the surface is held substantially vertically.
The methods and compositions of the invention are also non-corrosive, providing less than about 250 mils/year of steel reduction, in accordance with United States Department of Transportation Hazardous Material Regulation 173.136.
The compositions of the present invention are also non-corrosive to eyes of the user. Non-corrosive to the eyes refers to compositions that do not cause permanent corneal damage when evaluated according to the scale for scoring occular lesions in Draize et al., Method for the study of irritation and toxicity of substance applied topically to the skin and mucous membranes, J. Pharmacol. Exp. Ther. 1944, 82:377-390.
The present invention is also low-fuming. Low-fuming is described as used in the present invention refers to a product that produces little or no substantial fumes when applied to the surface of interest at the temperature of interest. Fume levels can be evaluated subjectively by noting the level of smell and irritants given off by the product upon application.
Fume levels may also be evaluated using head space GC analysis. GC analysis provides a quantitative amount of the chemical released that are considered to be inhalation irritants. Alternatively, fume levels can be measured using vapor pressure droplet size evaporation.
Preferred compositions according to the present invention exhibit few fumes at temperatures in excess of 100xc2x0 F., more preferably in excess of 150xc2x0 F., most preferably in excess of 200xc2x0 F.
According to one embodiment of the present invention, the compositions are substantially free of chlorine. As used herein, the term xe2x80x9csubstantially free of chlorinexe2x80x9d refers to a composition that has insufficient chlorine to have any irritating effects. More particularly, xe2x80x9csubstantially free of chlorinexe2x80x9d refers to a composition containing less than 0.1% chlorine.